During the past several years, jogging has become a particularly popular national pastime. People have become aware of potential health problems associated with lack of proper exercise, and special emphasis has been placed on working of the cardiovascular system. Jogging has grown to be a preferred type of exercise, since leg and arm muscles, in addition to the heart, are worked. Indeed, many physicians recommend jogging, with various degrees of strenuousness, to patients who have had cardiac problems.
Since the benefits from exercise such as jogging appear only when the exercise is faithfully repeated, a person must develop a habit or routine of exercise at least several times a week. In most cases, jogging is a difficult activity to fit into a regular routine. For example, running in the rain or snow, or intense heat, may be unpleasant and indeed dangerous. City dwellers may have to travel some distance to find a track or park suitable for jogging. Accordingly, many people begin a jogging routine with good intentions to continue, but find that the habit soon breaks down, and eventually disappears. Therefore, it is useful to have a device which can assist people to perform a jogging-type exercise in their home, and which is inexpensive and easily stored.
Indoor jogging devices have been proposed in the past. For example, Garcia, U.S. Pat. No. 3,628,791 discloses a jogging aid having a pair of foot pedals which are adjustably biased to support persons of different weights. The pedals are hinged at the front, and are depressed at the rear by the jogger when in use. This device is somewhat confining to the runner, since he must keep one foot on each pedal. In addition, the handrail could be easily bumped or kicked by a jogger in full stride.
A board for in-place jogging is shown in Childers, U.S. Pat. No. 3,634,895. This board consists of a piece of plywood supported by a layer of foam rubber to provide a degree of resilience to the board. The plywood is carpeted to provide a non-skid surface for the runner. Since all of the resiliency of the board is attributed to the foam, the amount which the board can "give" on any single impact is quite limited, particularly for a relatively small person.
Accordingly it is an object of the present invention to provide an in-place jogging device which is relatively inexpensive and attractive, and which is constructed to provide substantial platform movement for joggers of widely varying weights.
It is another object of the invention to provide a jogging platform having a spring construction which partially self-adjusts the travel of the board to the force applied to the board, providing good jogging action over a wide range of applied forces.